The present invention relates generally to an optical disk drive apparatus. More particularly, the invention relates to an improvement of an optical disk drive apparatus of a disk-exchangeable type in which a disk cartridge enclosing therein an optical recording medium such as optical disk or magneto-optical disk is exchangeably inserted into the disk drive apparatus.
Generally, in a disk drive apparatus of a disk-exchangeable type in which a disk cartridge enclosing therein an optical recording medium such as optical disk or magneto-optical disk is manually exchangeable with respect to a body of the disk drive apparatus, an ejecting operation for the disk cartridge from the disk drive apparatus is carried out by, for example, pushing an ejection button which projects from a front panel of the disk apparatus.
For this purpose, the disk drive apparatus is equipped with a disk loading mechanism including an ejecting means, when the ejection button is pushed, the ejection means of the loading mechanism serves to move upward the disk cartridge in order to remove the optical recording medium from a turn table attached to the tip end of a spindle motor which drives the optical recording medium for rotation, and then, the disk cartridge is ejected outward from the disk drive apparatus.
In an exemplary optical disk drive apparatus, when the ejecting button is pushed in the state that the spindle motor is operated to rotate the optical recording medium, the operation of the spindle motor is stopped after the disk cartridge is ejected. Therefore, when the disk cartridge is moved upward in the state that the optical recording medium is held for rotation on the turn table of the spindle motor, the optical recording medium collides with a central projecting portion formed on the disk cartridge while rotating within the cartridge, resulting in a generation of wear dust from the optical recording medium and the projecting portion of the cartridge. The wear dust may be attached to the recording surface of the optical recording medium or the surface of optical parts of an optical pickup head, causing the optical disk drive apparatus to generate a data error.
In order to reduce the amount of wear dust, it has been proposed an optical recording medium which is provided at a central portion thereof with a guard ring made of a material having wear-resistance properties, so that when the ejection operation is performed in the state that the spindle motor is operated, the guard ring can collide with the projecting portion of the disk cartridge.
Even in this case, however, the generation of wear dust from the projecting portion can not be prevented, and wear dust may also be generated from the guard ring, even though its amount is very little.
In order to prevent the generation of wear dust, it has been also proposed a optical disk drive apparatus comprising an ejection locking mechanism which uses, for example, a solenoid and is operative to lock the ejection means of the disk loading mechanism so as not to perform the ejection operation when the spindle motor is operated.
However, such an apparatus suffers from a disadvantage in that the ejection locking mechanism and the ejecting means of the loading mechanism may be suffered from a damage due to an excessive force applied to the ejection button when the ejection means is locked.
On the other hand, the optical disk drive apparatus of a disk-exchangeable type has many portions, each of which communicates the interior of the apparatus with the atmosphere, causing the atmosphere to flow into the interior thereof. In such a construction, dust contained in the atmosphere may be also attached to the surface of the recording medium or the surface of the optical parts of the optical pickup head, causing the optical disk drive apparatus to generate a data error.
In order to prevent the invasion of dust into the interior of the drive apparatus, it is considered to seal the whole of the disk drive apparatus with a surrounding cover.
In this case, however, the disk drive apparatus are provided at the inside thereof with many heat generating sources such as a laser diode which is used as a light source of the optical pickup head, a seek motor which serves to move the optical pickup head, a drive motor for moving objective lens of the optical pickup head, a spindle motor for rotating the optical recording medium, and driving circuits of these elements. Therefore, when the whole of the drive apparatus is sealed with the surrounding cover from the outside, a temperature in the interior of the drive apparatus tends to rise over a permissible temperature of the optical disk or the constituent elements of the disk drive apparatus, resulting in a deterioration thereof.
In order to restrain the rise of temperature in the interior of the disk drive apparatus, it is considered to forcedly cool the interior of the disk drive apparatus with the atmosphere drawn thereinto. However, when the atmosphere is drawn into the disk drive apparatus, dust contained in the atmosphere is also drawn into the apparatus, whereby the above-mentioned problems of dust may remarkably occur.
Further, when the speed of operation of the disk drive apparatus is increased, the amount of heat generated from the motors increases due to an increase of the amount of consumption of electric power of each of the above-mentioned motors and the drive circuits, resulting in a mach more rise of temperature in the disk drive apparatus.
Namely, in the case of an optical disk drive apparatus sealed with a surrounding cover, when the sealing degree is increased, the influence of the dust may be reduced due to a decrease of the amount of the atmosphere drawn into the apparatus, but the temperature in the interior of the apparatus rises over the permissible temperature. To the contrary, when the amount of the atmosphere is increased to reduce the rise of temperature in the interior of the apparatus, the influence of dust remarkably occurs, so that it has been difficult to realize simultaneously both the reduction of rise of temperature and the influence of dust.